Google reported that their site can harm your PC

31 Jan 2009 - Searching the word "Google", showed the following result.

Can Google.com site harm your computer? Probably not.  I guessed, the search engine must have hit a programming bug at that moment.  Every website it returned has the warning "This site may harm your computer". Google reported at everything is bad on the internet. After a couple of minutes, Google plug up this error and everything is back to normal. So for awhile on 31 January 2009, Google massive search was out of action.

Later in the day, Google spokeperson admitted it was "Human Error" when an internal list of harmful sites was updated.  A single forward slash (/) was put on the list in place of a full web address, effectively blacklisting every website because all web addresses contain the character. The problem was detected at around 2.30pm GMT on 31 January 2009 and was only fixed after 40 minutes.

Google Search malware warnings were based on a list of potentially harmful sites maintained with the help of a non-profit internet organisation called StopBadware.org.  StopBadware carefully researches each consumer complaint to decide fairly whether that URL belongs on the list. Google periodically receive updates to that list. It was on one of this update that Google blacklists entire internet.

Apart from lost advertising revenue, which one expert estimated to be about US$3million, this incident is embarrassing for the world's most popular search engine, known for its reliability.